Mendelevium (Md)
Mendelevium (Md) is element 101, an actinide. Atomic mass 258, configuration [Rn] 5f¹³ 7s². Properties, isotopes, oxidation states, uses and history, with an interactive 3D atom model.
Key facts
| Atomic number | 101 |
|---|---|
| Symbol | Md |
| Standard atomic weight | 258 |
| Category | Actinide |
| Period | 7 |
| State at room temperature | Solid |
| Electron configuration | [Rn] 5f¹³ 7s² |
| Valence electrons | 2 (Variable) |
| Common oxidation states | +3 |
| Common ions | No common ions |
| First ionization energy | 635 kJ/mol |
| Melting point | ~827°C |
Common uses
- Research only
Where it matters
- "Atom-at-a-time" synthesis (First element made this way)
Hazards
- Radioactive
History
| Discovered | 1955 |
|---|---|
| Discovered by | Ghiorso, Harvey, Choppin, Thompson, Seaborg |
| Name | Dmitri Mendeleev |